Tin-based catalyst for photodecomposition

By Tetsuo Satoh | November 1, 2016

Daylight-driven photocatalysts have attracted much attention in the context of “green” technology for reducing pollutants. Although a number of active materials have been reported and their applications are rapidly increasing, many are discovered after enormous experimental efforts. Now, Isao Tanaka and colleagues at Kyoto University (Kyoto; www.kyoto-u.ac.jp), in collaboration with the Tokyo Institute of Technology (TiTech) and the Nagoya Institute of Technology (NiTech), have discovered a new photocatalyst system by using a highly efficient screening system based on theoretical calculations. The “discovered” catalyst — Sn(II)-based oxides, β-SnMoO4 — was subsequently synthesized and shown to have the predicted photocatalytic activity. This catalyst was found after a “rational search” of 3,483 known and hypothetical compounds with various compositions and structures over the whole range of pseudo-binary systems, SnO-MOq/2, where M = Ti, Zr and Hf (with q = 4); M = V, Nb and Ta (with q = 5); and M = Cr, Mo and W (with q = 6). Screening was performed using thermodynamic stability, band gap, and band-edge positions by density-functional-theory calculations, which identified β-SnMoO4 as a potential target. Then, a low-temperature…